Polyaminophenol oxidation hair dyes



United States Patent 3,134,721 POLYAMINOPHENOL OXIDATION HAIR DYES John Robert Seemuller, Maisons-Lafitte, Seine-et-Oise, France, assignor to LOreal, a corporation of France No Drawing. Filed Dec. 7, 1959, Ser. No. 857,988 Claims priority, application France Nov. 25, 1955 6 Claims. (Cl. 167-88) This invention relates to the dyeing of animal fibres, and more especially the dyeing of live hair, by the use of polyaminophenol compounds and derivatives thereof.

It has long been known to etiect the dyeing of hair with the aid of so-called oxidation dyes, which are not true dyes but products which, on oxidation, give coloured derivatives. The known oxidation dyes are generally aromatic polyamines and/or polyaminophenols.

Generally in using oxidation dyes a solution of such a dye is mixed, a short time before use, with an oxidizing solution, for example dilute hydrogen peroxide, and the mixture is then applied to the hair to be dyed. Satisfactory results are obtained, but this method offers the disadvantages that the treatment is of excessively long duration, the hydrogen peroxide tends to act deleteriously on the substance of the hair during the application, and it is necessary to store the working solutions in separate bottles.

It has been found that polyaminophenols of the general formula:

wherein R and R each represent a hydrogen atom, a lower alkyl group or a lower hydroxyalkyl group; and X represents a halogen atom, or an amine, hydroxyl, carboxyl, lower alkyl, lower alkoxy or nitro group, the nitro group with the additional feature that at least one out of the two radicals R R each represent a hydrogen atom, or else if X represents a hydrogen atom provided that at least one among said radicals R R is other than a hydrogen atom, have remarkable properties as oxidation dyes for the dyeing of animal fibres and more especially of the human hair. The said compounds oxidize rapidly in the air so that the use of an auxiliary oxidizing agent, such as hydrogen peroxide, is avoided, together with the concomitant disadvantages referred to above.

According to the present invention therefore, a process for dyeing live hair, comprises applying to the fibres a solution of a compound of the aforesaid general formula, allowing the oxygen of the ambient air to act on the hair impregnated with the compound for a time sufficient to the desired development of the shade, and thereafter rinsing the hair.

An aqueous solution of these compounds or of their derivatives is prepared, the pH of the solution is adjusted with the aid of an alkali, for example ammonium hydroxide, and the solution is applied to the fibres to be dyed, for example to the human hair. By simple exposure to the ambient air, the fibre is dyed to a shade depending upon the derivative chosen. The process is very simple, avoids the use of an oxidizing agent such as dilute hydrogen peroxide, and permits dyeing at room temperature.

The present invention further provides compositions for application to animal fibres for dyeing the same, comprising an aqueous solution of a compound of the aforesaid general formula adjusted to a pH value of 5 to 8.

3,134,721 Patented May 26, 1964 ice IOH

There is employed as starting substances 2:4-diaminophenol, which is first acetylated to protect the two amino groups. 2:4-diacetylaminophenol, melting at 122 C., is thus obtained in a yield of 94% of the theoretical yield.

This compound is nitrated by means of a mixture of concentrated nitric and sulphuric acids at a temperature below 5 C. The product is poured on to crushed ice and the precipitate obtained is filtered and washed with water. On recrystallization, there is obtained, in a yield of 6-nitro-2:4-diacetylarninophenol, melting at 214 C.

This product is deacetylated by heating it on the Water bath in a hydrochloric acid medium for half an hour. Crystals of 6-nitro-2:4-diaminophenol monohydrochloride are obtained, in a yield of 76%.

Dyeing.-A 3% aqueous solution of 6-nitro-2z4-diaminophenol monohydrochloride is prepared and adjusted to a pH of 8 with ammonium hydroxide. This solution is applied to live hair and a dark brown shade with a reddish tinge is obtained.

In an alternative procedure the pH of the solution is adjusted to a value of from 5 to 6 with the aid of an organic acid, such for example as citric acid. A shade of identical tone is then obtained, but this develops more slowly.

In both cases, the development of the shade can be accelerated by the addition of dilute hydrogen peroxide. The final shade is substantially identical to that obtained without hydrogen peroxide.

EXAMPLE II Preparation of 2:4:6-Triamin0phen0l NHsa Picramic acid (2-amino-4:6-dinitrophenol) is reduced by heating with hydrochloric acid and tin powder. The chlorostannate formed is displaced by zinc, and the tin which precipitates is separated by filtration. Concentrated hydrochloric acid is then added to the filtrate and 2:4:6-triaminophenol trihydrochloride then precipitates in the form of white needles in a yield of 83%.

Dyeing.A 3% aqueous solution of 2:4:6-triaminophenol trihydrochloride is prepared and neutralized by means of ammonium hydroxide.

This solution is applied to the hair and a greenishblond tint is obtained.

The addition of hydrogen peroxide accelerates the development and deepens the shade.

3 EXAMPLE In 1 .'2 -Dihydrxy-3 -Diamin0benzene I NHZ Dinitropyrocatechol diacetate (M.P. 124 C.) is simultaneously reduced and deacetylated by treating it with hydrochloric acid and stannous chloride under heating. The chlorostannate thus formed precipitates by strong acidification with hydrochloric acid. The tin is then displaced by means of zinc and the hydrochloride of the base is reprecipitated by adding concentrated hydrochloric acid.

This hydrochloride is obtained in the form of a white powder which decomposes at about 225 C. to 230 C.

Dyeing.A 3% aqueous solution of this hydrochloride is prepared and is brought to BS by means of ammonia and immediately applied to the hair. On oxidation in contact wtih the ambient air, the hair is dyed a greenish blond.

EXAMPLE IV 183 g. (1 mole) of 2:4-dinitroaniline are dissolved in 1200 ml. of glacial acetic acid. This solution is heated to 60 C. and a solution of 192 g. of bromine in 200 ml. of glacial acetic acid is gradually added. The mixture is maintained at the ter'iperature of 60 C. for 8 hours, and then allowed to cool. The bromo derivative, which crystallizes on cooling, melts at #153 54 C. The yield is about 70%. This bromo derivative (170 g.) is introduced into a round flask equipped with a reflux condenser and containing 1400 ml. of a 5% aqueous solution of potassium hydroxide. The mixture is refluxed for 1 hour. After cooling, the phenolate precipitates and is converted into the corresponding phenol by acidification with hydrochloric acid. 6-bromo-2z4-dinitrophenol melting at 1161 l7 C. is obtained. The yield is 90%. This compound is reduced by any conventional method of reducing nitro compounds to give amino compounds. The sulphate of the amine is formed. Since this sulphate is only slightly soluble in cold water, it is recrystallized from water. A white powder very faintly tinged with pink, the alkaline solutions of which oxidize very rapidly in open air, is thus obtained. The yield is 75%.

Dyeing-3 g. of 6-bromo-2:4-diaminophenol sulphate are dissolved in 100 ml. of water. At the time of application of this solution to live hair, it is adjusted to pH 8 by adding ammonia. After exposure to ambient air for 10 to minutes, the hair is dyed in a beautiful brown shade having a violet tinge.

EXAMPLE V 6-Meth0xy-2:4-Diaminophen0l EXAMPLE VI 3 :5 -Diamin0salicylic Acid HO O C NH;

3 :S-dinitrosalicylic acid is reduced by means of tin and hydrochloric acid. After neutralization and acidification by means of sulphuric acid, the sulphate is obtained as a white powder which is insoluble in water and difficultly oxidizable when dry. The yield is 60%.

Dyeing.-3 g. of the powdered sulphate are introduced into ml. of water. The addition of ammonia immediately before the application to the hair and in sulficient quantity to bring the pH to 8 produced complete dissolution of the powder. The hair impregnated with the resulting solution is dyed a beautiful ash-blond shade on mere exposure to the air for :10 to 15 minutes.

EXAMPLE VII 6-Methyl-2.'4-Diamin0phen0l 1130- NHQ 4-nitro-orthotoluidine is heated for several hours with a 15% potassium hydroxide solution. The corresponding phenol melting at 94 C. is quantitatively obtained. This phenol is treated with a sulphuric/nitric acid mixture to form the dinitro derivative. On reduction, the desired diamine is obtained, which is isolated in the form of its sulphate.

Dyeing.By dyeing live hair by the general method of operation described in the foregoing examples and simple exposure to the ambient air, a beautiful mahogany shade is obtained without any necessity to apply hydrogen peroxide.

In order to clearly show the particular possibilities of the use of the compounds according to the invention, all the dyeing tests described in the foregoing examples were carried out without any oxidizing agent other than atmospheric oxygen.

This application is a. continuation-in-part of my copending application Serial No. 623,773, filed Novem,- ber 23, 1956, now abandoned.

What is claimed is:

1. A process for dyeing live human hair which comprises, applying thereto an aqueous solution as an oxidative dyestuff containing 6-nitro-2:4 diaminophenol, thereafter said hair is oxidized to promote the development of the dyestuif before the hair is rinsed.

2. A process for dyeing live human hair which comprises, applying thereto an aqueous solution as an oxidative dyestuif containing 2:4:6-triaminophenol, thereafter said hair is aerated to promote substantial oxidation of this compound before being rinsed.

3. A process for dyeing live human hair which comprises, applying thereto an aqueous solution as an oxidative dyestuff containing 1:2-dihyd1-0xy 3:5 diaminobenzene, thereafter said hair is aerated to promote substantial oxidation of this compound before being rinsed.

4. A process for dyeing live human hair which comprises, applying thereto an aqueous solution as an oxidative dyestuff containing 6-methoxy-2:4-diaminophenol, thereafter said hair is aerated to promote substantial oxidation of this compound before being rinsed.

5. A process for dyeing live human hair which comprises, applying thereto an aqueous solution as an oxidative dyestuif containing 3:5-diaminosalicylic acid, thereafter said hair is aerated to promote substantial oxidation of this compound before being rinsed.

6. A process for dyeing live human hair Which comprises, applying thereto an aqueous solution as an oxidative dyestuff containing 6 methyl 2:4 diaminophenol, thereafter said hair is aerated to promote substantial oxidation of this compound before being rinsed.

6 References Cited in the file of this patent UNITED STATES PATENTS (2nd addition to No. 43 8,476) OTHER REFERENCES Heilingotter: Am. Perfumer and Ess. Oil Review, May 1954, pp. 345-348.

Zemplen et al.: Chemical Abst., vol. 49, 1955, col. 8484b.

Chem. Abst. vol. 49, 1955, col. 4429b. Kass: Part II, Am. Perf. and Aromatics, 68:2, August 1956, pp. 34-37, esp. Table 6. 

2. A PROCESS FOR DYEING LIVE HUMAN HAIR WHICH COMPRISES APPLYING THERETO AN AQUEOUS SOLUTION AS AN OXIDATIVE DYESTUFF CONTAINING 2:4:6-TRIAMINOPHENOL, THEREAFTER SAID HAIR IS AERATED TO PROMOTE SUBSTANTIAL OXIDATION OF THIS COMPOUND BEFORE BEING RINSED. 